Composite cathode active material, method of preparing the same, and cathode and lithium battery including the composite cathode active material

Patent metadata

Field	Value
Publication number	US-10109851-B2
Application number	US-201414567818-A
Country	US
Kind code	B2
Filing date	Dec 11, 2014
Priority date	Feb 10, 2014
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A composite cathode active material includes a material capable of intercalating or deintercalating lithium; and a solid ion conductor. A cathode and a lithium battery each include the composite cathode active material. A method of preparing a composite cathode active material includes: mixing a core including a cathode active material and a solid ion conductor; and forming a coating layer including the solid ion conductor on the core utilizing a dry method.

First claim

What is claimed is:

1. A composite cathode active material comprising:
a material capable of intercalating or deintercalating lithium; and
a solid ion conductor, wherein the solid ion conductor comprises particles having two or more size groups, each size group has different average particle diameters,
wherein the solid ion conductor comprises a NASICON-type lithium ion conductor represented by Formula 2 below:
Li 1+Z Ma x Mb 2−x (PO 4 ) 3   Formula 2

wherein Ma and Mb are each independently at least one selected from the group consisting of Zn, Cd, Ni, Mn, Co, Fe, Sc, Ti, V, Cr, Al, In, Ga, Y, Lu, Zr, Hf, Sn, Si, Ge, V, Nb, Ta, Sb, and As, and 0≤x≤0.8, and 0≤z≤0.8.

2. The composite cathode active material of claim 1 , wherein the solid ion conductor has a bimodal particle diameter distribution comprising greater-diameter particles and smaller-diameter particles.

3. The composite cathode active material of claim 1 , wherein:
a core comprises the material capable of intercalating or deintercalating lithium, and
a coating layer is on at least a portion of the core, and
the coating layer comprises the solid ion conductor.

4. The composite cathode active material of claim 3 , wherein the coating layer connects a plurality of cores.

5. The composite cathode active material of claim 3 , wherein the solid ion conductor of the coating layer comprises smaller-diameter particles.

6. The composite cathode active material of claim 4 , wherein the solid ion conductor of the coating layer connecting the cores comprises greater-diameter particles.

7. The composite cathode active material of claim 5 , wherein an average particle diameter (D50) of the smaller-diameter particles is 10 μm or less.

8. The composite cathode active material of claim 6 , wherein an average particle diameter (D50) of the greater-diameter particles is greater than 10 μm and equal to or less than 100 μm.

9. The composite cathode active material of claim 1 , wherein an amount of the solid ion conductor is 10 wt % or less based on a total weight of the composite cathode active material.

10. The composite cathode active material of claim 1 , wherein an amount of the solid ion conductor is 6 wt % or less based on a total weight of the composite cathode active material.

11. The composite cathode active material of claim 1 , wherein the solid ion conductor further comprises at least one selected from the group consisting of a NASICON-type lithium ion conductor, a thio-NASICON-type lithium ion conductor, a garnet-type lithium ion conductor, a perovskite-type lithium ion conductor, and a lithium phosphorous oxynitride (LiPON)-type lithium ion conductor.

12. The composite cathode active material of claim 1 , wherein the solid ion conductor comprises at least one selected from the group consisting of LiTi 1.2 Sn 0.8 (PO 4 ) 3 , Li 1.5 SnTi 0.5 Al 0.5 (PO 4 ) 3 , Li 1.3 Ti 1.7 Al 0.5 (PO 4 ) 3 , LiAlO 2 , Li 3 PO 4— Li 4 SiO 4 , Li 1.3 La 0.3 Ti 1.7 (PO 4 ) 3 , and La 0.5 Li 0.5 TiO 3 .

13. The composite cathode active material of claim 3 , wherein the material capable of intercalating or deintercalating lihtium comprises a compound represented by one of Formula 3 to 7 below:
Li x Co 1−y M y O 2−a X a   Formula 3

Li x Ni y Co z M 1−y−z O 2−a X a   Formula 4

Li x Mn 2−r M r O 4−a X a   Formula 5

Li x Co 2 −r M r O 4−a X a   Formula 6

Li x Me y M z PO 4−a Xa  Formula 7

wherein: 0.90≤x≤1.1, 0≤y<1, 0≤z<1, 1−y−z>0, and 0≤a≤2, and 0≤r<1,
Me comprises at least one metal selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Al, Mg, Zr, and B,
M comprises at least one element selected from the group consisting of Mg, Ca, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al, Si, Ni, Mn, Cr, Fe, Mg, Sr, V, and a rare-earth element, and
X comprises at least one element selected from the group consisting of O, F, S, and P.

14. A cathode comprising the composite cathode active material of claim 1 .

15. A lithium battery comprising the cathode of claim 14 .

Assignees

• Samsung Sdi Co Ltd

Inventors

• Song Yu-Mi
• Hong Ming-Zi
• Park Do-Hyung
• Kwon Seon-Young
• Moon Joong-Ho
• Han Ju-Hyeong
• Park Han-Eol
• Kim Min-Han
• Kim Kyoung-Hyun
• Kim Ki-Hyun
• Kim Sang-Hoon

Classifications

• H01M4/366 Primary

  as layered products · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M4/1391

  of electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M2300/0071

  Oxides · CPC title

• H01M4/131

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title